(CNN) A blast of severe winter weather last week caused thousands of Southwest Airlines flight cancellations and spiraled into a complete meltdown of its flight system. In the days since, the carrier's scramble to recover has been slow and, some passengers argue, largely unsuccessful. But experts say Southwest's mess is actually the culmination of issues that have been building over several years.
Since Dec. 22, the beleaguered airline has canceled more than half of its typical flight schedule, and by late Wednesday about 87% of all canceled flights in the US were from Southwest alone, according to industry trackers FlightRadar24 and FlightAware.
The dire situation, which has exasperated passengers and caught the eye of government regulators, has magnified this week as other major airlines recovered from the extreme cold, ice and snow that gripped much of the United States over the holiday weekend.
The company has apologized to its passengers and employees for the daily cancellations and reduced its capacity by roughly two thirds on Thursday, according to a CNN review of flight data.
This week's meltdown is not the first time the company has found itself in this predicament. In October 2021, Southwest canceled more than 2,000 flights over a four-day period. While the airline blamed the crisis partly on bad weather in Florida, Southwest canceled flights for far longer than its competitors.
But much of Southwest's mess may be the result of long-term problems unrelated to the weather.
Chief among them are outdated internal processes and information technology. Southwest's scheduling system hasn't changed much since the 1990s, according to Captain Casey Murray, president of the Southwest Airlines Pilots Association.
Southwest has also acknowledged the company's outdated infrastructure. "We've talked an awful lot about modernizing the operation, and the need to do that," CEO Bob Jordan told employees in a memo obtained by CNN.
Over the years, the airline's cancellation rate has crept up, tripling from 2013 to September 2022, the most recent data available from US Bureau of Transportation Statistics, which tracks the airlines' performance, and well before the recent crisis.
The bureau has only released data for 2022 through September. To ensure a fair comparison, CNN only analyzed the carrier's data from January to September in previous years.
Cancellation rates among airlines fluctuate year-to-year, depending on weather and other factors, such as Covid-19, which resulted in a major industry-wide disruption in the early months of the pandemic in 2020.
But Southwest has consistently failed to perform as well as its competitors when it comes to cancellations, according to bureau data.
In several years over the last decade, the airline had higher cancellation rates compared to other major airlines, the data shows.
It's not just cancellations. Southwest has also seen its on-time percentage slide in recent years to the lowest point in a decade. Through September of 2022, well before the carrier's current struggles, only about 7 in 10 of its flights have arrived on time.